Crystal formation in biological systems has attracted many researchers over the years because of the enhanced structural properties—mechanical (Fratzl and Weinkamer, 2007; Berman et al., 1990; Miserez et al., 2009; Weaver et al., 2012), optical (Levy-Lior et al., 2010; Levy-Lior et al., 2008) and magnetic (Kirschvink and Gould, 1981)—of its outcome compared to non-biogenic crystals. Arguably by far the most research in the field has been focused on biogenic calcium carbonate and its properties (Sommerdijk and de With, 2008; Weiner and Addadi, 2011; Dunlop and Fratzl, 2010; Estroff, 2008; Gower, 2008). Particular attention has been directed to biogenic calcite owing to its enhanced fracture toughness, shown to originate as a result of the deflection of propagating cracks away from the pronounced cleavage planes (Berman et al., 1988; Chernov, 2003). This is achieved by the presence of intracrystalline proteins and organic molecules within individual crystals in directions oblique to the (104) cleavage plane of calcite (Berman et al., 1988). These intracrystalline molecules have also been shown to strongly influence crystal shape, morphology (Aizenberg et al., 1996) and coherence length (Berman et al., 1993; Aizenberg et al., 1995). Another outcome of their presence is the existence of systematic anisotropic lattice strains (Pokroy et al., 2004; Pokroy et al., 2006a). We have shown that incorporation of proteins and even of single amino acids into calcite grown synthetically leads to similar lattice strains (Pokroy et al., 2006b; Borukhin et al., 2012). Kim et al. showed that by mimicking proteins with micelles or polymer particles that become incorporated into calcite it is possible to reproduce lattice strains and, moreover, to enhance hardness of the calcite (Kim et al., 2011; Kim et al., 2010). Similar results were obtained in a study by Schenk et al. using polyelectrolytes (Schenk, 2012). It was also shown that an agarose gel can be incorporated into single crystals of calcite (Li and Estroff, 2009). Colfen et al. showed that amino acids affect the early stages of calcium carbonate formation (Picker et al., 2012). A partial but deeper understanding of what governs the incorporation of biological molecules into calcium carbonate was recently achieved after mapping of the incorporation of the 20 common amino acids into synthetic calcite (Borukhin et al., 2012). As revealed by Wenger et al. with respect to crystallization of non-biogenic ZnO, the addition of synthetic latex particles can influence both the morphology as well as the optical and paramagnetic properties of the crystals due to latex incorporation (Muñoz-Espí et al., 2007; Muñoz-Espí et al., 2006).